We're Open
+44 7340 9595 39
+44 20 3239 6980

# [Solved]1. Altering a text encrypted with an AES key under CBC.

100% Pass and No Plagiarism Guaranteed

### [Solved]1. Altering a text encrypted with an AES key under CBC.

1. Altering a text encrypted with an AES key under CBC. [10%]

You are given an encryption of the message below, encrypted with an AES key (which you are not given) using CBC with PKCS5 padding.

Advance 5km East with all due speed: 7:00 on 2nd

a) Give a ciphertext (encrypted under the same AES key) in which 7:00 has been changed to 8:30 in the plaintext. [4%]

b)State what other parts of the plaintext will change as a result of the change in (a). [2%]

c) Explain why you cannot use the approach used to solve part(a) to change the word speed to the word haste within the plaintext. [4%]

2. RSA [10%] You are given an RSA public key (exponent and modulus), and a plaintext encrypted using the Javax implementation of RSA/ECB/NoPadding with that key.

There are two ways you can approach this problem:

(1) factorise the modulus of the public key to obtain p and q, then compute (p-1)(q-1) and work out the private key from that, to decrypt the ciphertext

(2) Use a dictionary attack (the coursework website provides a dictionary: english.txt)

a) Use one of these methods to obtain the plaintext, and explain why the approach you use is better than the other one. [5%]

b) Explain how you applied your method to this problem. [5%]

Get answer to the whole question for just £999

100% Plagiarism Free & Custom Written,

International House, 12 Constance Street, London, United Kingdom,
E16 2DQ

## STILL NOT CONVINCED?

View our samples written by our professional writers to let you comprehend how your work is going to look like. We have categorised this into 3 categories with a few different subject domains

View Our Samples

#### We offer a £ 2999

If your assignment is plagiarised, we will give you £ 2999 in compensation

Nov,09,2018

Nov,09,2018

Nov,09,2018

### Details

• Title: [Solved]1. Altering a text encrypted with an AES key under CBC.
• Price: £ 989
• Post Date: 2021-09-30T12:01:15+00:00
• Category: Assignment Requirements
• No Plagiarism Guarantee
• 100% Custom Written

### Customer Reviews

[Solved]1. Altering a text encrypted with an AES key under CBC.
Reviews: 5

### A masterpiece of assignment by Izkiyah , written on 2020-03-12

The support team is quite friendly and gives you the best solutions. I literally came here crying and went smiling like an idiot. My HR assignment is written beautifully with all the specifications I wanted. This is the best platform to get helped in assignments for me. All the people are supportive. Keep it up you all!
Reviews: 5

### A masterpiece of assignment by Kylie , written on 2020-03-12

I have tried other sites for assignment help but the result that Insta Research has produced outweighs others. Since I am weak at writing and shaping the data logically, I am glad I took help from this site. Thanks to my writer for such a great quality of the assignment in Business.